a) Field of the Invention
The present invention relates to a magnetic head slider and its manufacture, and more particularly to a magnetic head slider and its manufacture capable of preventing accidental breakage of the head and variation of the flying characteristics of a slider.
b) Description of the Related Art
As shown in FIG. 2A, a slider 10 having magnetic heads is supported by a suspension 12 over a magnetic disk 14 loaded in a hard disk drive. As the magnetic disk 14 rotates, the slider 10 flies over the disk 14 to record information in the disk 14 or reproduce it from the disk 14. If an external shock is applied to the flying slider 10, the position of the slider 10 changes.
As shown in FIG. 2B, if the slider 10 together with the suspension 12 jumps from up the disk 14 by external shock, it lands thereafter to onto the disk 14 by reaction as shown in FIG. 2C. In this case, the magnetic head slaps the surface of the disk 14. This head slap may cause damages of the disk surface or breakages of the slider.
In order to avoid surface damages of the disk 14 and breakages of the slider 10, a countermeasure as illustrated in FIGS. 3A and 3B has been used. FIG. 3A is a bottom view of a slider, and FIG. 3B is a cross sectional view taken along line IIIBxe2x80x94IIIB in FIG. 3A. Air bearing surfaces (ABSs) 18 and 20 of rails formed on a disk facing plane 16 of the slider are chamfered and rounded at their entire peripheries 28 to form chamfered portions 22. These chamfered portions 22 relax local impact to be applied to the surface of the disk 14 when head slap occurs, to thereby prevent surface damages of the disk 14 and breakages of the slider 10. In contrast outermost edges 29 of the slider 10 are not chamfered at all.
An edge blend method has been used as a method of forming chamfered portions. As shown in FIG. 4, an abrasive tape 24 is softly pushed against ABSs 18 and 20 of the slider 10 and the whole surfaces 28 of ABSs 18 and 20 are rubbed to form the chamfered portions 22.
It is an object of the present invention to provide a magnetic head slider capable of preventing damages of the disk surface and breakages of the slider to be caused when the slider slaps the disk surface by external shock, and of preventing variation of the flying characteristics of the slider.
It is another object of the present invention to provide a method of manufacturing a magnetic head slider capable of preventing electrostatic discharge damages (electrostatic breakage) of a magnetic head element and deterioration of the magnetic characteristics of magnetic material.
According to one aspect of the present invention, there is provided a magnetic head comprising: a) a slider having an air bearing surface (ABS) formed to project on a disk facing plane which is to confront a magnetic disk, wherein the slider having a second surface and the ABSs projecting from the second surface; and b) chamfered portions formed by chamfering three-dimensional corners constituting inner and outer corners of the ABSs and outer corners of the second surface of the slider, wherein two-dimensional corner lines constituting the side edges of the ABS and the second surface being remained non-chamfered.
According to another aspect of the present invention, there is provided a method of manufacturing a slider type magnetic head comprising: forming a projected air bearing surface (ABS) having an edge at its periphery, by etching a disk facing plane of a magnetic head slider, which is to confront a magnetic disk; coating on the disk facing plane with liquid resin and drying the coated resin, the resin thickness at three-dimensional corners constituting corners of the ABS being set thinner than other portions of the ABS; etching the resin by bombarding milling particles to the disk facing plane, etching the three-dimensional corners which is gradually exposed by the milling to chamfer the three-dimensional corners, and stopping bombarding the milling particles before two-dimensional corner lines constituting the side edges of the ABS are etched or before etching the two-dimensional corners progresses substantially; and a step of removing the resin left on the disk facing plane after said etching step.
Liquid resin can be coated on the disk facing plane having ABSs with a peripheral edge so that the resin film thickness becomes thin at the three-dimensional corners because of a balance of surface tension and dropping (gravity) of resin. In this state, milling particles are bombarded so that etching the three-dimensional corners can be progressed with a priority over the other portions to chamfer the three-dimensional corners. As being different from the process using an abrasive tape, this method does not use a rubbing process so that it is possible to prevent breakage of an magneto-resistance (MR) element and deterioration of the magnetic characteristics of magnetic material to be caused by electrostatic charge. This method is therefore applicable also to MR heads (inclusive of GMR heads).
If the coated liquid resin is heated, its fluidity increases and a difference of a resin film thickness between the three-dimensional corners and other portions can be made large. Therefore, only the three-dimensional corners can be reliably chamfered. If the etching is performed under the condition that the pole tip surface of a magnetic head element mounted on the slider is covered with the resin, it is possible to prevent the pole tip surface from being etched.